3KPX:
reference: NMR-derived Topology of a GFP-photoprotein Energy Transfer Complex., Titushin MS, Feng Y, Stepanyuk GA, Li Y, Markova SV, Golz S, Wang BC, Lee J, Wang J, Vysotski ES, Liu ZJ, J Biol Chem. 2010 Dec 24;285(52):40891-900. Epub 2010 Oct 6. PMID: 20926380

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